As the instrument device of this type such as an instrument device of an automobile, as disclosed in, for example, the following Patent Literature 1, an instrument device is known which has an indicator needle installed in an instrument main part, an indicator panel having an indicator portion such as a scale, a letter, and a number that are to be indicated by the indicator needle, a donut-shaped translucent substrate disposed on the indicator panel, and a light source that supplies light beam to the translucent substrate.
According to this instrument device, the translucent substrate is illuminated by the light beam which is supplied to the translucent substrate, and the indicator panel and the like are illuminated by the light beam which goes out from the translucent substrate to the exterior.
Therefore, a stereoscopic effect can be obtained by superimposing the indicator panel and the translucent substrate, and the translucent substrate and the indicator panel can be illuminated.